Monitor and secondary display switched. 580 card,DisplayPort/HDMI

I have a Dell 5675 with a 580 card. I added a DisplayPort to HDMI adapter and connected it to my 55 in. LG OLED TV. After rebooting PC the OLED became the main display and the monitor is secondary. I want to use the monitor (1080) for main and and when playing games switch to the OLED (4k). How can I flip it back?